Devices are known for fitting lids made of a complex of aluminum and of plastic, e.g. a complex of aluminum and polyethylene. In particular, devices are known for fitting capsules which are stamped in a capsule press and which are placed on bottlenecks by means of a chute and an applicator device.
Bottles that have received a capsule are conveyed to a heat-fusing device where the capsule is welded onto the bottleneck in autogeneous manner by means for heating the capsule and applying pressure thereto. That solution requires a capsule to have a skirt for the purpose of holding the capsule on the bottleneck while it is being transferred to the welding station, which implies that the capsule has sufficient thickness of metal to enable it to be shaped by stamping.
A device is also known, in particular from Document FR-A-2 290 389 for closing receptacles by welding flat lids obtained from a strip of heat-fusible material, said device including a roll of heat-fusible material in strip form, a member for supporting the end of the strip so that the end of the strip is cantilevered out therefrom, a member for placing receptacles so as to bring receptacles successively up to the support member, and a weld head disposed to move vertically above a receptacle that has been put in place. In that device, the strip is cantilevered out above the receptacle by means of a stepper advance member which pays out a determined length of strip over the receptacle, said length being sufficient to form a lid, the strip then being sectioned at the member for supporting the end of the strip to cut off a segment which is fixed to the neck of the receptacle by the weld head.
Such a method also assumes a sufficient thickness of metal on the strip to impart sufficient stiffness to the strip to enable the length required for making a lid to be capable of being cantilevered out before it is cut off. The closure strip is thus thicker than is strictly necessary for providing a sealed closure of the receptacle. In addition, the metal that provides adequate stiffness for the strip is not suitable for recycling, and as a result receptacles fitted with lids of this type are themselves not recyclable.